A slot coat gun with a slot nozzle assembly is a contact or non-contact application device that extrudes a fluid material onto a substrate in a filmlike or stripelike manner. A slot coat gun can apply a fluid material thinly and broadly on the face of Kraft paper, high-quality paper, mold release paper, polyethylene film, non-woven fabric, etc., and so is used for manufacturing Kraft bags, adhesive tape and labels, hygienic articles, etc.
A slot coat gun can be used for applying a foam melt material to a substrate (Patent Document 1).
The slot nozzle assembly of a slot coat gun that extrudes a foam melt material has a shim plate. Herein below, a slot nozzle assembly 41 that has a conventional shim plate 44 shall be described with reference to the attached drawings.
FIG. 6 is an exploded perspective view of a conventional slot nozzle assembly 41. FIG. 7 is a vertical cross-section view of the conventional slot nozzle assembly 41 taken along line VII-VII in FIG. 6. FIG. 8 is a drawing showing the shim plate 44 that is attached to a conventional rear nozzle block 43.
The conventional slot nozzle assembly 41 comprises a front nozzle block 42, the rear nozzle block 43, and the shim plate 44, which is disposed between the front nozzle block 42 and the rear nozzle block 43.
The front nozzle block 42 is provided with a plurality of foam melt material passages 45. The plurality of foam melt material passages 45 respectively communicate with a plurality of material entrance ports 45a provided in the upper face of the front nozzle block 42 and a plurality of material exit ports 45b provided in the rear face of the front nozzle block 42.
The shim plate 44 is provided with a plurality of material passage holes 44a and a shim opening 44b that is a rectangular cutout. When the shim plate 44 is incorporated in the slot nozzle assembly 41, the plurality of material exit ports 45b of the front nozzle block 42 respectively face the plurality of material passage holes 44a of the shim plate 44. The foam melt material flows from the material exit ports 45b and into the material passage holes 44a of the shim plate 44.
The rear nozzle block 43 is provided with a plurality of material vertical groove passages 46 and a single common horizontal groove passage 48. When the rear nozzle block 43 is incorporated in the slot nozzle assembly 41, the plurality of material passage holes 44a of the shim plate 44 respectively face the upper part of the plurality of material vertical groove passages 46 of the rear nozzle block 43. The foam melt material flows from the material passage holes 44a of the shim plate 44 and into the material vertical groove passages 46 of the rear nozzle block 43.
The slot 49 is demarcated by the shim opening 44b of the shim plate 44, the rear face of the front nozzle block 42, and the front face of the rear nozzle block 43.
The foam melt material is supplied from a control module (not shown in the drawing) to the material entrance ports 45a of the front nozzle block 42. The foam melt material passes through the material passages 45 of the front nozzle block 42 and flows from the material exit ports 45b into the material passage holes 44a of the shim plate 44. Then the foam melt material flows from the material passage holes 44a into the vertical groove passages 46 of the rear nozzle block 43.
The foam melt material that flowed into the vertical groove passages 46 flows into the common horizontal groove passage 48, and then flows into the slot 49. Ultimately, the foam melt material is extruded from an exit port 50 of the slot nozzle assembly 41. The foam melt material that is extruded from the exit port 50 foams, and forms a broad striplike foam layer 56 on a substrate 55 that is being conveyed in conveyance direction X.